1. Field of the Invention
This invention provides in-line roller skates that have a control wheel mounted either forward or rearward of one or more intermediate wheels. The intermediate wheel or wheels provide primary support for the user, and the control wheel provides improved thrusting or braking.
2. Brief Description of the Prior Art
In-line roller skates became popular several years ago and are used widely for pleasure skating and recreational skating. These in-line roller skates are characterized by a construction in which three or more wheels are located longitudinally along the boot of the skate so that all of the wheels rotate in the same rotational plane. In-line skates differ from the more conventional roller skate that has front and rear axles with wheels at the ends of each axle; in the conventional skate the wheels on the left side of the axles rotate in the same rotational plane while the wheels on the right side rotate in a parallel but different rotational plane.
In-line roller skates offer greater skating versatility and more skating style options than conventional roller skates. In-line skates are more useful on sidewalks, streets, bicycle paths, and parking lots. The skates are similar to ice skates but with wheels in place of the blade and in-line skating techniques traditionally are similar to ice skating style. In-line skates enable users to participate in hockey games, acrobatics, races, and many other athletic activities.
The art of conventional roller skates developed several mechanisms for selectively preventing the front pair of wheels from rotating in a rearward direction. One of these mechanisms is shown in U.S. Pat. No. 4,553,767 Robjent et al in which a pawl can be moved by the skate operator into or out of a ratcheting position in which a spring biases the pawl into contact with teeth that are attached to and rotate with the wheels. When the pawl is in the ratcheting position, wheel rotation in the forward direction moves the pawl away from the teeth, but when the wheels attempt to rotate in the rearward direction, the pawl is drawn into the teeth to effectively lock the wheel and prevent rotation in the rearward direction.
A different mechanism for achieving the same result is shown in U.S. Pat. No. 4,526,389 Chase in which supplemental rollers are mounted eccentrically on a shaft positioned behind the front wheels of a roller skate. A spring forces the rollers into contact with the front wheels. During forward rotation of the wheels of the roller skate, the rollers rotate eccentrically away from the wheels and enable normal operation. Rearward rotation of the wheels causes the rollers to rotate into engagement with the wheels and thereby causes braking to prevent any significant rearward motion of the skate.
U.S. Pat. No. 4,289,323 Roberts provides a disk shaped rotor attached to the front wheel of a roller skate and a disk shaped stator attached to a rotationally stationary portion of the skates. A bearing cage supporting several ball bearings is located between the rotor and stator. The stator has a plurality of teardrop-shaped cavities that receive the ball bearings and permit the balls to rotate freely in a forward direction. When the wheel is rotated in a rearward direction, the balls are forced along a ramp in the cavity that eventually locks the rotor and stator and prevents rearward movement. Roberts also shows an arrangement in which ball bearings are arranged cylindrically around an axle. The ball bearings are located in a teardrop shaped cavity. Under certain forces, the ball bearings roll into the narrower dimensions of the cavity and wedging action prevents further wheel rotation.
Advantages taught by the art for these roller skates include facilitated learning to roller skate, improved ability to skate uphill and move up stairways, undefined improvements in safety and reductions in energy requirements and bodily strain, and improved skating style.